I want to buy another house but I cant sell my first house.?

I have a house before i was married wasnt able to sell it, although I tried. now we rent it to a tenant for about 2 years (no intentions of leaving for the most part). we currently stay in my FIL property (bad neighbor hood, no space). we need to move on . Looked to rent but the rent is double the mortgages out there (3 bedroom 2 baths) on home. I need some advice. I did get preapproved for another home loan. Were looking into auctions or maybe just buying another house..What do I do?